The present invention relates generally to an apparatus for the examination of the heats of transformation of material samples and, in particular, relates to such an apparatus having a test sample receiver for a test sample, a reference sample receiver for a reference sample, means for cooling or heating both the test and reference samples and a measuring device which responds to differences in the heating up characteristic of the test and reference samples.
M. L. Clarebrough et al., in "The Determination of the Energy Stored in a Metal During Plastic Deformation" (Proc. of The Royal Society, 1952, Vol. A 215, pp. 507-524), describe a device for continuous and measurable variation of the temperature of a test sample and a reference sample. In that device respective heating elements serve to heat the test sample and the reference sample. These heating elements are arranged in heater circuits with a part common to both heating elements. A control loop, including sensors for measuring the temperature difference between the test and reference samples, adjusts this temperature difference to zero by varying the energy supply to the heating element associated with the test sample. Thereby the difference of the energy supplied to the test and the reference samples, which energy is measured with a highly precise differential wattmeter, provides a measure of the heats of transformation.
Another apparatus of the present type is illustrated and described in German Auslegeschrift 1 473 303. Therein small heating plates for accommodating a test and a reference sample are arranged side by side and spaced from each other in a housing.
The known apparatus permits only individual measurements with which the test and reference samples are inserted by hand into the apparatus.